Ask a business of any size who is responsible for the domain and you get one of three answers. A confident wrong one. A vague gesture towards IT or the web person. Or a pause, followed by the realisation that nobody has thought about it in years.
The third answer is the most common and the most honest.
Why this specific gap exists
Most business functions have an owner because they have a rhythm. Payroll happens monthly. Invoices go out and come in. Someone notices when they stop.
Domain infrastructure has no rhythm. It is set up once, usually during a website project, by whoever was doing the website project. Then it works for years while nobody touches it. There is no monthly moment where a person looks at it and confirms it is fine, because there is no reason to.
The absence of a rhythm means the absence of an owner. And the absence of an owner means that when it eventually breaks, the failure is discovered by a customer rather than by the business.
The three moments where it goes wrong
Somebody leaves. The domain is on their account, the certificate renewal runs on a server they configured, the mail provider was set up with their login. None of it was written down because it never needed to be while they were there. Their successor inherits a working system and no map of it.
A supplier changes. A new agency takes over the website. They get access to what they need for the website, which is not the same as access to what the business depends on. The domain stays with the previous agency, sometimes on a personal account, occasionally with someone who is now a competitor.
A card expires. The most mundane and the most common. Auto-renew has been doing its job for four years without anyone thinking about it, the card is reissued, the charge fails, and the failure notice goes to the same unread address as everything else. Nothing announces that the reassuring confirmations have stopped arriving.
Why organised businesses are worse at this
This is the part that surprises people. It is tempting to assume domain lapses happen to businesses that are generally disorganised, and it is largely the opposite.
A one-person business usually has the domain on the owner's own account, paid on the owner's own card, with notices arriving at an address they read. Fragile in other ways, but the person and the process are the same entity.
A business with staff turnover, delegated responsibilities and multiple suppliers has more places for the thread to break. Every handover is an opportunity for something that was working to stop being anyone's job. Organised businesses fail here precisely because they distribute responsibility, and this particular responsibility never got distributed to anyone.
The failures are not really technical
Look at what actually breaks and none of it is difficult.
A domain expires because a notice went to the wrong inbox. A certificate stops renewing because a migration left the job behind. Mail authentication breaks because someone edited DNS for an unrelated reason and nobody recorded what it said before. A subdomain points at a cancelled service because cancelling and deleting the record are two actions and only one of them was on anyone's list.
Every one of those is an organisational gap wearing technical clothes. The fix in each case takes minutes. The reason it does not get fixed is that nobody knows it needs fixing.
What follows from this
If the problem is that nobody owns it, then buying a tool does not solve it either. A monitoring dashboard that nobody logs into is the same gap in a different shape.
What works is making the information arrive rather than waiting to be fetched. One email a week that says everything is fine, and an immediate one when it is not, does not require anybody to own anything. It requires somebody to read an email, which is a much lower bar and one that survives staff changes.
The second thing that works is writing it down somewhere that outlives the person. Not because documentation is virtuous, but because the specific failure here is knowledge leaving with a person, and a record is what makes that survivable.
Neither of those is a clever solution. They are both quite boring. That is appropriate, because the problem is boring too, and it costs businesses real money precisely because it is too boring for anyone to have claimed it.